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Sweet potatoes can (usually) be found in the exotic produce section of the grocery store. They've been spotted at Carrefour, Auchan, Intermarché and even Ed and Spar.
Look for a section within the produce marked exotique that has items such as star fruit, ginger root, plantains, etc... They're called patate douce and are usually around 3euros/kilo.
If you can't find them there, try an African import store...or use carrots instead !
American recipe: Sweet potato casserole
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4 cups sweet potatoes (cooked, peeled, and mashed)
2 Tbsp butter
2 eggs, beaten
1/2 cup milk
1 teaspoon vanilla
1/4 cup sugar
1/2 cup brown sugar
1 cup coconut
3 tablespoon butter, melted
In a large mixing bowl, combine mashed sweet potatoes, margarine, eggs, milk, vanilla and sugar. Mix well. Spread into a greased 1 1/2-quart casserole.
Prepare the topping by mixing the coconut, brown sugar and butter. Sprinkle over the potatoes.
Bake at 350 degrees for 25 minutes or until heated thoroughly.